Diversified energy giant Exxon Mobil has a reputation as one of the savviest capital allocators in the industry. No better example of its foresight into industry trends is the 2009 purchase of XTO Energy, which along with Chesapeake, was one of the largest owners of U.S. natural gas reserves. The deal was completed in June 2010 for $41 billion and immediately made Exxon one of the biggest beneficiaries of the revival in U.S. production. Given Exxon's total current market capitalization of more than $400 billion, investors will obviously gain exposure to its global reserve, production and refining capabilities. The XTO deal offers investors the opportunity for diversified exposure to more unconventional development, including shale gas and the potential to export U.S. natural gas to other countries through the use of liquefied natural gas. Overall, Exxon sells at a very reasonable forward price to earnings (P/E) ratio of 10, offers decent income potential with a current dividend yield of 2.2% and should be capable of growing earnings close to 10% annually for the foreseeable future.